Abrading apparatus for mold platens



Nov. 1, 1955 2,722,090

V. H. HASSELQUIST ABRADING APPARATUS FOR MOLD PLATENS Filed Jan. 21, 1954 2 Sheets-Sheet 1 IN VLN TOR. Dr: 70/ 1Q f/25551 QL/IE 7- HTTV 1955 v. H. HASSELQUIST 2,722,090

ABRADING APPARATUS FOR MOLD PLATENS Filed Jan. 21, 1954 2 Sheets-Sheet 2 INVENTOR. Zlrzrmq ALL #5551. qurs 7' United States Patent ABRADING APPARATUS FOR MULD PLATENS Victor H. H'asselquist, Akron, Ohio, assignor to The B. F. Goodrich Company, New York, N. Y., a corporation of New York Application January 21, 1954, Serial No. 405,305

6 Claims. (Cl. 51170) This invention relates to an improved surface dressing machine which is particularly useful for abrading and polishing the molding faces of vulcanizing press platens while these platens are installedin a press.

The molding faces of the platens of a vulcanizing press ordinarily become corroded and pitted after periods of operation, and because of the weight of these platens it is not feasible to remove them from the presses each time the molding faces require refurbishing. The tools which have been proposed heretofore for re-surfacing platens without removing the platens from the press have been too unwieldy for a single operator to control effectively and have required considerable time and labor to accomplish the resurfacing.

According to this invention, a tool is provided for this purpose which is highly maneuverable within the relatively narrow opening between a pair of opposed mold platens while they are installed in a press, and which a single operator may easily control on either of the opposed molding faces of a pair of platens. The apparatus of this invention includes a carriage structure for supporting the abrading mechanism on the lower mold surface while the operator operates the mechanism to clean the upper mold surface. The abrading mechanism is designed so that it is removably engageable with the carriage and to clean a lower platen the abrading mechanism is disengaged from the carriage and inverted. The abrading mechanism further includes means to support the abrading mechanism in an inverted position for translational movement on the mold face of the lower platen to effect the cleaning.

The invention will be more fully described in connection with the accompanying drawings which illustrate a preferred apparatus constructed in accordance with and embodying the principles of this invention.

In the drawings:

Fig. 1 is an elevational view of a typical vulcanizing press with its platens opened and with the apparatus of this invention in operating position for abrading the molding face of the upper platen;

Fig. 2 is a plan view of the apparatus with portions broken away;

Fig. 3 is a side elevation of the apparatus with portions broken away and showing the carriage mechanism separated from the abrading mechanism;

Fig. 4 is a cross-sectional view taken along the line 4-4 of Fig. 3; i

Fig. 5 is an enlarged detail view taken along the line 55 of Fig. 4; and

Fig. 6 is a fragmentary detail view showing the arrangement of the disc-supporting means and the abrasive disc, the view being drawn on an enlarged scale.

The illustrated embodiment of the invention includes an abrading mechanism 10 which is removably engageable with a carriage 11 as shown in Figs. 1, 3 and 4. The structure of the abrading mechanism 10 includes a circular abrasive disc 12 driven by an air motor 14. The radial center of the disc 12 is fastened to the end of the movement in a generally vertical plane by an upper link 18 and a lower link 19 which are each fork-shaped as shown in Fig. 2. The legs of the upper link 18 have a pair of laterally-spaced forward ends 22 which flare outwardly to embrace the opposite sides of the housing of the motor 14 and which are connected by a pair of pivots 24 to the housing of the motor. Similarly, the legs of the lower fork-shaped link 19 have a pair of laterallyspaced forward ends 25 (see Fig. 3) which flare outwardly to embrace the opposite sides of the housing of motor 14 and these ends 25 are connected by a pair of pivots 27 to the housing of the motor.

The links 18 and 19 each extend rearwardly from the motor 14 in spaced generally parallel relation to each other and their rearward ends 28 and 29, respectively, are supported by a generally rectangular frame 30 (see Fig. 4). The frame 30 has a pair of upright side members 31 connected together by a transverse upper member 32 and a lower member 33 to define an opening 34 through the frame. The side members 31 are spaced apart slightly wider than the legs of the links 18 and 19 so that the rearward ends of these links extend through the opening 34 of the frame close to the upright side members 31. The rearward end 28 of link 18 is connected to the frame 30 by a rod 36 which extends through and is fastened to each leg of the link and which has a pair of projecting ends 37 pivotally supported in the upright side members 31 near the upper member 32 of the frame. The portions of link 19 embraced by the upright side members 31 of the frame are connected together by a transverse brace 39 having a pair of axially aligned trunnions 40 at its opposite ends which are pivotally supported by the upright side members 31 near the lower member 33 of the frame. The upper link 18 is slightly shorter than the lower link 19 so that when the links are swung upwardly the peripheral edge portion of the abrasive disc 12 farthest from the frame 30 will strike the nected at the outer end of the handle from a source of compressed air. The air introduced into the handle through the connection 46 is conducted to the motor 14 through a conduit 49 which extends from the cross member 42 in communication with the tubular handle 45 to the housing of the motor 14. The handle is also provided with a fitting 47 having a nozzle 48 directed toward the abrasive disc and adapted to blow abraded particles away from the operator when the apparatus is in operation. The outer end of the handle is provided with a suitable valve 50 to regulate the flow of air into the handle.

Between the abrasive disc 12 and the pivots 24 which connect the upper link 18 to the housing of motor 14, there is an annular tray 51 which has an outside diameter slightly larger than the diameter of the disc 12. The tray 51 is a fiat metal plate with an upturned flange 52 around its periphery and it is rigidly secured to the housing of the motor by the bolts 53 (Fig. 3) so that it concentrically surrounds the rotor 16. This tray collects abrasive particles from the disc 12 as the disc is worn andalso serves as a bumper to prevent the edges of the disc from being moved against the polished vertical guides of aplaten press on which the platens are slidably supported.

The details of the structure of the abrasive disc 12 are best shown in Fig. 6. The disc includes a thin circular backing plate 54 of highly flexible spring steelhaving a plurality of radial slots 55 extending through the marginal area 56 from the peripheral edge 57 of the backing plate. This plate has a generally flat center area 59 disposed coaxially about the rotor 16 of the motor, and the surrounding marginal area 56 is curved generally convexly relative to a moldface. That is to say the marginal area 56 is curved gradually upwardly from the flat area 59 and then reversely curved downwardly to the peripheral edge 57 in substantially an elongated ogee curve to provide the contour in a radial direction shown in Fig. 6. The side of the backing plate which is directed away from the motor 14 is covered with a rub ber pad 62 and over this pad there is disposed a flexible circular sheet 63 of abrasive material. The sheet 63, the pad 62, and the backing plate 54 are collectively secured at their centers to the end of the rotor 16 by a nut 65 the head of which is recessed slightly below the surface of the abrasive sheet 63 on the flat area 59 of the backing plate so that the nut can not engage the work surface.

The slots 55 and the contour of the marginal area 56 of the backing plate permit the portion of the abrasive disc in contact with the mold face to flatten against a mold face when the disc is urged into contact with it. The resilience of the backing plate 54 eliminates the shattering and excessive lateral vibration which would otherwise occur if the disc were rigid. Also because of the flexibility of the backing plate, the abrasive disc is adapted to conform to concavely curved surfaces and the like in the molding faces if any such surfaces are present.

To aid an operator in controlling the abrading action of the apparatus, a coil spring 68 (see Fig. 3) is stretched between the tray 51 and the transverse brace 39 which extends between the rearward ends 29 of lower link 19. The spring tension normally tends to maintain the links 18 and 19 in a horizontal position and when the links are pivoted upwardly to raise the motor 14, the spring is elongated to resist this movement. If the operator releases the pressure on the grip at the end of the handle while the motor 14 is raised, this spring 68 immediately retracts the abrasive disc from the face of the mold. Since the tension in the spring resists the movement of the handle to raise the motor, the possibility that an operator may inadvertently bring the abrasive disc into contact with the mold face while he adjusts the apparatus in certain positions relative to the mold face is greatly reduced.

When the abrading mechanism 10 is utilized as in Fig. 1 for abrading and polishing a molding face 70 of an upper platen 71 of a typical vulcanizing press 72, the abrading mechanism 10 is supported for maneuvering relative to the platen on the portable carriage 11. The carriage is formed with structural frame members 75 arranged in a rectangular form and is provided at its front corners with ball casters 76 rotatably mounted in sockets 77, and with small wheels 78 at its rear corners for supporting the frame members on a plane surface. As indicated in Fig. 1, the carriage 11 is adapted to rest on the mold face 79 of the lower platen 80 when the upper platen is to be refurbished and the casters 76 and the wheels 78 allow the carriage to be moved translationally over this face and maneuvered easily in any direction.

The abrading mechanism 10 is connected to the carriage by a pair of vertical posts 82 of equal length. These posts fit slidably into sockets 83 at the rear corners of the carriage near the wheels 78 and their upper ends project above the carriage and are engageable with a pair of spaced sockets 84 (see Fig. 4) which are supported by brackets 85 fastened to the side members 31 of the frame 30. Each of the posts has a central collar 86 surrounding it against which the bottom of the sockets 84 abut when the abrading mechanism is engaged with the carriage. When the apparatus is not in use, the bottom of the air motor 14 normally fits through the opening defined by the frame members 75 at the front of the carriage and rests on the surface engaged by the casters 76.

Since the distances to which the platens may be separated in different types of presses may vary considerably, the apparatus is designed so that the abrading mechanism may be supported at various elevations above the carriage by substituting other pairs of posts for the posts 82. Thus in Fig. l, the abrading mechanism is shown supported an appreciable distance above the carriage by posts 82a which are longer than the posts 82 and which are engageable with the sockets 83 and 84 as explained in the foregoing. The sockets 83 on the carriage which receive the lower ends of the posts. are located forwardly of the rearward supporting wheels 78 to minimize the tendency for the front end of the carriage to tilt upward from the lower platen when the motor is raised by the handle to urge the abrasive disc against the mold face of the upper platen 71.

To abrade a mold face of a lower platen such as the mold face 79 of the lower platen 80 in the press of Fig. l, the abrading mechanism 10 is disengaged from the posts 82a and then inverted so that the abrasive disc 12 is directed against the molding face 79. In this position of the abrading mechanism, the frame 30 is supported on the mold face for translational movement by a pair of rollers 88 mounted on the brackets 89 opposite the sockets 84. The action of the abrading mechanism when cleaning an upwardly-directed molding face is substantially the same as explained in the foregoing.

Variations of the structure disclosed may be made within the scope of the appended claims.

I claim:

1. Apparatus for abrading a mold face comprising a carriage, a frame removably supported on the carriage at one end of the carriage, a rotatable abrasive disc supported above the carriage at the end of the carriage opposite the frame and having an abrasive surface directed upwardly away from the carriage, means extending between said frame and the disc for supporting the disc for movement in a vertical plane toward and away from the carriage, and means on the opposite side of said frame from the carriage for supporting the frame in an inverted position for translational movement when the frame is disengaged from the carriage.

2. Apparatus for abrading a mold face comprising a carriage, a rotatable abrasive disc above the carriage having an abrasive surface directed upwardly away from the carriage, means for rotating said disc, a frame removably engaged with the carriage, a pair of links each having one end pivotally connected to the frame and having its opposite end pivotally connected to said means to support said disc, the links being movable arcuately about the frame to move the abrasive disc in a vertical plane relative to the frame, a handle for moving said links arcuately relative to the frame to bring said abrasive surface of the disc against a mold face, a spring for opposing said movement of the links and means on a side of the frame opposite the carriage for supporting the frame in an inverted position for translational movement against a mold face when the frame is disconnected from the carriage.

3. Apparatus for abrading a molding face comprising a carriage, a frame removably engageable with the carriage, a motor having a rotor disposed generally perpendicular to the carriage-and to the surface of the mold face to be abraded, a pair of links each pivotally connected at one end to the motor and at the opposite end to the frame for arcuate movement relative to the frame to move the motor in a vertical plane relative to the carriage, a flexible resilient disc secured to said rotor and directed upwardly from the carriage, the disc having an abrasive surface disposed in a plane substantially parallel to the work surface and in face-to-face relation to the work surface, means for moving said links pivotally relative to said frame to move said abrasive surface of the disc away from the carriage and toward said work surface, a spring for opposing said arcuate movement of said links, and rollers on a side of the frame directed away from the carriage for supporting the frame in an inverted position for translational movement when the frame is disengaged from the carriage.

4. Apparatus for abrading opposed molding faces in a platen press comprising a carriage having a forward end and a rearward end, a first set of rollers mounted at the rearward end of the carriage, a pair of castors mounted at the forward end of the carriage, a frame above said carriage having a side removably engaged with the car riage at a point on the carriage intermediate said rollers and the casters but adjacent the rearward end, a pair of links pivotally secured to the frame and extending forwardly from the frame toward the forward end of the carriage, an abrasive disc supported by said links above the forward end of the carriage and adapted for arcuate movement in a vertical plane relative to said frame and for rotation about an axis substantially perpendicular to the carriage, an abrasive surface on the disc directed away from the carriage, and on the frame a second pair of rollers on a side thereof opposite said side engaged with the carriage for supporting the frame in inverted position for translational movement when the frame is disconnected from the carriage.

5. Apparatus for abrading a molding face comprising a carriage, a frame removably engageable with the car riage, a fluid-operated motor having a rotor disposed generally perpendicularly to the carriage and to the surface of the mold face to be abraded, a pair of links each pivotally connected at one end to the motor and at the opposite end to the frame, one of the links being disposed above the other in spaced parallel relation and the links being movable about their respective pivots arcuately relative to the frame to move the motor in a generally vertical plane relative to the carriage, a flexible resilient disc secured to said rotor on the end of the rotor and directed upwardly from the carriage, the disc having an abrasive surface disposed in a plane substantially parallel to the work surface and in face-to-face relation to the work surface, a handle for moving said links pivotally relative to said frame to move the disc away from said carriage, the handle being tubular and extending from said motor through said removable frame and being secured to the lower of said links and through which handle fluid is supplied to said motor for driving the disc, a spring for opposing said arcuate movement of said links, and rollers on a side of the frame directed away from the carriage for supporting the frame in an inverted position for translational movement when the frame is disengaged from the carriage.

6. Apparatus in accordance with claim 5 which further includes a nozzle mounted in said handle and directed toward said disc for blowing abrasive particles from the disc when the disc is engaged with a mold face.

References Cited in the file of this patent UNITED STATES PATENTS 409,051 Maloy Aug. 13, 1889 1,134,925 Soderlund Apr. 6, 1915 1,936,449 De Marchi Nov. 21, 1933 2,114,966 Myers Apr. 19, 1938 2,124,705 Locklin July 26, 1938 2,394,858 Jefireys Feb. 12, 1946 84,906 Pond et a1. Oct. 18, 1949 2,670,577 McDonough Mar. 2, 1954 

